Chapter 6, Lesson 1

Fossils

Chapter 6, Lesson 1

Pages 222-227

What are fossils?

Fossils are the preserved remains or traces of living things

Most fossils form when living things die and are buried by sediment. The sediment slowly hardens into rock and preserves the shapes of the organisms

Sediment is made up of rock particles or the remains of living things

What are fossils?

Most fossils form from animals or plants that once lived in or near quiet water where sediment builds up

Only hard parts of organisms generally leave fossils because the soft parts decay or are eaten by other organisms

Multiple Choice

What is the first action that must occur for an organism to become a fossil?

• an organism dies

• the organisms is covered by sediment

• sediment hardens into rock

Multiple Choice

What is the second action that must occur for an organism to become a fossil?

• an organism dies

• the organisms is covered by sediment

• sediment hardens into rock

Multiple Choice

What is the third action that must occur for an organism to become a fossil?

• an organism dies

• the organisms is covered by sediment

• sediment hardens into rock

What are the kinds of Fossils?

Fossils found in rock include molds and casts, petrified fossils, carbon films, and trace fossils. Other fossils form when the remains of organisms are preserved in substances such as tar, amber, or ice.

Molds and Casts

Molds - a hollow area in sediment in the shape of an organism or part of an organism

A mold forms when the organism is buried in sediment

Cast - a solid copy of the shape of an organism

Molds and Casts can preserve fine details

Petrified Fossils

Petrified Fossils - fossils in which minerals replace all of an organism, or a part such as a dinosaur bone

Water carrying minerals seeps into spaces in cells and later evaporates leaving just the minerals

Carbon Films

Carbon Film - an extremely thin coating of carbon on rock

When sediment buries an organism, some gases escape leaving carbon behind

Trace Fossils

Trace Fossils - provide evidence of activities of ancient organisms

Footprints, trails, and burrows are examples of trace fossils

Preserved Remains

Preserved Remains are the entire organism - this often happens when the organism gets trapped in sticky tar or tree resin (amber). Ice can also preserve remains of organisms

Multiple Choice

The preserved remains or traces of living things.

• evolution

• geology

• fossils

• extinct

Multiple Choice

A hollow area in sediment in the shape of an organism or part of an organism is ________.

• a cast

• a mold

• a petrified fossil

• a trace fossil

Multiple Choice

What type of fossils provide evidence of the activities of ancient organisms?

• molds and casts

• carbon films

• petrified fossils

• trace fossils

Multiple Choice

What type of fossil is this?

• petrified

• mold

• cast

• carbon film

Multiple Choice

What type of fossil is this?

• petrified

• mold

• cast

• carbon film

Multiple Choice

What type of fossil is this?

• petrified

• mold

• cast

• carbon film

Multiple Choice

What type of fossil is this?

• body fossil

• trace fossil

Multiple Choice

A(n) __________ is an extremely thin coating of carbon on rock.

• mold

• carbon film

• cast

• petrified

Multiple Choice

Which of the following substances is not able to preserve entire organisms?

• sticky tar

• water

• amber

• ice

What do Fossils Show?

Paleontologist - scientist who studies fossils

The fossil record provides evidence about the history of life and past environments on Earth. The fossil record also shows how different groups of organisms have changed over time

Fossils and Past Environments

Paleontologists use fossils to picture Earth's past environments and climates

Coal is found in Antarctica but coal forms from the remains of plants that grow in warm climates

Change and the Fossil Record

Evolution - change in living things over time

Extinct - when a type of organism no longer exists and will never again live on Earth

Scientists use fossils to reconstruct extinct organisms and determine how they may be related to living organisms

Multiple Choice

The term __________ is used to identify a scientist who studies fossils.

• anthropologist

• biologist

• geologist

• paleontologist

Multiple Choice

Scientists study the ________ to learn about the history of life, past environments on Earth, and how different groups of organisms have changed over time.

• atmosphere

• fossil record

• moon

• ocean floor

Multiple Choice

____________ is the gradual change in living things over long periods.

• Evolution

• Extinction

• Life cycle

• Mutation

Multiple Choice

An organism is __________ if it no longer exists and will never live again on Earth.

• evolved

• extinct

• adapting

• changing